Though enforcement of the blue slip process has varied since it was created in 1917 — for many years it largely just allowed home state senators to advise the Judiciary Committee of their views of a judicial nominee — it has, at times, permitted a home state senator to veto anyone nominated to a federal judgeship in their state. At some points in the Senate’s history, including right now under Senate Judiciary Chair Patrick Leahy (D-VT), the chair of the Judiciary Committee would refuse to schedule a confirmation hearing on a judicial nominee if one or both of the nominee’s home-state senators objected to them.

In 2003, however, when Hatch became Judiciary chair and George W. Bush was president...